Mac 512k and SE "developer" units?

[tdiaz]

Format an 800K disk:

Drag System Folder to it.

It appears that there is more than 800K on the hard drive, of course, but not -much- more.

Do NOT do much if anything else with the drive, if you want to explore it with something to see if there's anything deleted that's recoverable.

IF the System Folder itself is too big for a floppy, start on the inside of it, leaving out other drivers, fonts, etc.

Do you have the ability to make disk images of the floppies you have?

I'd definitely be curious to see them .. The odds of being closely located are probably not great at all, but I'm in southern California, and could help with all of it, imaging, checking out the HD contents, making new boot disks, etc.

The SE can probably be a better candidate for setting up disks, especially if you've got a hard drive inside it, (I know, two drive slots, but it still could have a hard drive in there).

..and if you've got a way to get disk images onto it, to write them. Like a Localtalk network.

 

[crecords]

I still need to replace the battery on the se one of the floppy's makes a racket so I don't know if the se will be functional yet. I will see if I have a floppy to use for the backup.

 

[Anonymous Freak]

I received the new battery today and put it in and to my surprise it works!! I have not boot disk but it boots up to the external drive which also works! Could someone tell me how to make a boot disk from the external drive and back it up to a floppy? The floppy works, some of the disks I have work and some dont. I bet the printer works too, we will see.

If that's the "512k" system, then it's really a 512ke - the regular 512k can't boot System 6. It also means it has an 800k floppy drive, rather than the 512k's 400k drive. That will make life a lot easier than if it were an original 512k system.

 

[crecords]

It is a 512k that has been upgraded modified and tweeked. It has 4mb of memory but I think it may have a 407 drive. I'm booting from the external hard drive and it gives me the option to format a double sided disk but will only format one side. I will have to work on the se soon.

 

[tdiaz]

The photo of the 512 interior shows an 800K drive.

It's got the SCSI port, so that means it's got Mac Plus ROMs, making it a "512e", with the clip on board also having 4MB, it's effectively equal to a Mac Plus with 4MB. Software wise, short of some specific niche test for that clipped on hardware, there is no functional difference between this and a Mac Plus, and software that generalizes, finding Mac Plus ROMs with a memory amount available over 512K would report it as a Mac Plus.

If you can't format double sided, the drive or the disks are bad. The second side would be the top head.

Though it's not likely a physical problem with the top head, maybe a dirt problem. The top head acts as the pressure pad against the other head and if it were not deformed or sprung upwards, then the lower head would probably not read either, resulting in nothing working.

 

[crecords]

What is the easiest way to clean the floppy drive head?

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I guess I have some confusion concerning the 512ke. It was introduced in 1986 and this unit was made in 1984, I thought this started out as a 512k and some one upgraded it to be equal with the future e model.

 

[tdiaz]

A cleaning disk will usually do the job. Try to format, or boot it, a few times.

If it's really bad - you'll have to do it by hand. But ..

For some, that's not something I'd recommend.

but I will say this. If you do it, -DO NOT LIFT THE TOP HEAD- more than it already moves by itself.

I'm not kidding.

As for the 512e .. Enhanced.

Macintosh, M0001 came out in 1984.

In late 1984 the 512K option was added. The "Fat Mac". Prior to that, skilled hardware hackers had already figured out how to do it, and for around $600 street price, you could have your motherboard modified. Companies like Levco started out doing this kind of thing. Eventually going on to make more stuff.

With the addition of 512K, there were now two Macintosh models.

Macintosh was now Macintosh 128 and Macintosh 512.

In January 1986, the Mac Plus was introduced, after a few months prior the Mac 128 model was dropped. The Mac Plus brought Double Sided disks. 800K, HFS, SCSI and mini-din serial ports.

Third parties & hardware hackers figured out that copying the ROMs from a Plus, putting them on the motherboard and installing an 800K drive gave you double sided disks. Alas, in April 1986, Apple rolled out an official upgrade path for existing 512's. Swap the ROMs and disk drive, and get 800K support.

This, coupled with the sandwiched SCSI port, which just sits in the ROM sockets, with the ROMs placed on the SCSI board, added SCSI to the Mac 512e, the same way the Mac Plus had it.

Levco, Dove, General Computer/GCC among others made snap on, stack on, kinds of cards that added things from more RAM, the SCSI port, external video displays. There are 68020 cards, etc. All kinds of stuff to shove in there.

So, what you have is an original 512 that someone added a HyperDrive to, and then changed that Hyperdrive out for a SCSI drive later on. The fan, is from the original HyperDrive install, and when the drives went bad, most just ditched the fan as it was nothing but a noisy piece of junk in and of itself. Plus the way it was installed there, it's a great finger salad shooter.

When you get a chance, get some photos of the motherboard removed from the bottom. The added on card is a curiosity of some of the folks here, myself included.

Depending on what you have, it may be SCSI and video, or that plus RAM, or all those are separate parts in there.

 

[crecords]

I have tried to remove the motherboard and I don't think I can without breaking it. The connector for the extra monitor port is in the way of sliding it out. I took some pictures of the the extra board plus some of the cool disks that came with this computer. I will have to purchase a disk cleaner.

 

[crecords]

more pics

 

[tdiaz]

To get the motherboard out, after pulling off the power supply cable, and disconnecting from the back of the disk drive, the board would just slide back until you see the edges match up with the cutouts.

But since it has that board stacked on top of it, that doesn't always feel like it's going to work. A lot of times you just have to pop it out by prying the sides apart. It sounds worse than it actually is.

The board in there looks like an UltraMac 4096 / SCSI / External Display.
It's from the 1990 era, probably early 1991. The question is, is the display a mirror of the internal, or added desktop space. Without seeing more of the hardware, it's not easy to tell. With the age of the PCB, it may even be VGA, hence the connector, where using a monochrome VGA monitor would be the most optimal setup, and I've seen them used in that exact way, with a 640x480 and 800x600 setup.

The HyperDrive remains in sticker form only.

I thought it wasn't the older bridge board controller originally just because of the LSI Logic part that was visible in one of the earlier images as well. That's too new era wise for the HyperDrive.

Aside from the MiniDin 8, you have a "Mac Plus", in that package, with an added display function.

 

[crecords]

It is amazing someone would upgrade this unit in 1990 6 years after it was first made, considering the technology at that time. With all of the modifications made to this does it have any monetary value at this point? Also is it it unusual to find a disk stamped for campus use only? First year of apple link 1985

 

[Anonymous Freak]

It is amazing someone would upgrade this unit in 1990 6 years after it was first made, considering the technology at that time. With all of the modifications made to this does it have any monetary value at this point? Also is it it unusual to find a disk stamped for campus use only? First year of apple link 1985

It's basically a 512 upgraded to be a Plus now. It has some monetary value, but not as much as if it were a completely-stock 512.

 

[tdiaz]

Yes, as a non-molested Mac 512, it would be worth more. With that big hole bored in it .. OTOH ;-)

But like I've said all along, it's a nice set of period stuff, that if you wanted to assemble separately, you'd be spending lots more than you did to get it. I don't jump at Mac stuff much, and I would have thrown down that to get it.

 

[MacTech68]

I think the upgrade board is a rare beast. I can't find anything on the Calmos CD601C-3.

I suspect it's a top of the range upgrade, and maybe by 1990 it was being discounted heavily.

Most upgrades only had SCSI and RAM, so the added VGA port makes it rare IMHO.

tdiaz is correct, you can usually get them out by sliding the board until the cutouts at the left & right edges of the motherboard match the cutouts of the metal frame and sometimes spreading one side of the frame allows the motherboard to drop out.

 

[firewood]

Developer 512K

IIRC, there was a Macintosh Developer program circa 1984, where if you joined the program, you could buy a 512K "Developer Mac" at a discount price direct from Apple. It was the same model as the retail Mac though. Late 1984 thru '86. Most of the 512K's seem to have been upgraded circa 1986 to 512Ke's, with newer ROMs and disk drives.

 

[crecords]

mac se upgrades

Here are some pictures of the inside of the SE, there are two upgrades from cabletron 1989. I disconnected power to the noisy floppy, it dings on startup but there is nothing from the crt. There is still juice in the battery but would a bad battery cause no picture at all on the crt?

 

[MacTech68]

Nice pics. Seems like a simple Ethernet/AUI upgrade card - handy for networking, that's for sure.

Be very careful of the circuit board on the back of the tube. Don't knock it with your hand when working on the MacSE, or you could break the tip off the tube, rendering it useless.

On that note, I've known MacSEs to have that circuit board work loose in transit. You could try gently pushing it back squarely onto the tube and re-testing. Also, removing the upgrade board from the motherboard as a test measure to eliminate it as a possible cause.

After that, try powering it on with the rear case off in a dimly lit room and check that you see a faint orange glow from rear of the tube - you may need to observe from different angles to see it. If you can't see it, then the heater voltage is missing.

You can also try over-cranking the "Screen" voltage for a few seconds and see if the raster comes up (a dark glow with bright lines, slightly angled from horizontal). Don't leave it there for too long. If you see them, then most of the high tension & sweep is working, and it's time to delve into the video circuit and amps.

Also, of course you've tried turning the brightness knob on the front.

 

[crecords]

OMG Really I am not an idiot, you know what they say never assume anything. Just because I was told it was not functional I should have check the most basic thing first. It was the brightness!!! Yes I am laughing at myself, oh well.

 

[crecords]

The good news is they both work. This one also has to boot from the external drive. I plugged in a Ethernet cable to my router and the expansion card lit up. I tried to format a double sided disk and it would only format one side.

 

[tdiaz]

..and FWIW, a battery on an an SE, or any B&W compact Mac is not a show stopper at power up.

My rule when an SE*/30 or Classic/II is open is to pull off that PCB on the CRT as soon as the case back is cleared and set down.

On the 3.5" drive, if you're the mechanically inclined type:

http://www.kansasfest.org/2012/08/2010-diaz-maintenance/

I typically do the whole drive in about 5 minutes, and can do it really fast as a fun "demo", down to every piece removed, cleaned and put back.

This is based on some even more ancient pages I put up a -long- time ago..

http://apple2.org/35Drv/index.html

The 1.44MB drive is pretty close to the same thing, with just slight differences in the way the top part of the mechanical is engaged.

 

[MacTech68]

It's all good. I'm sure all techies have been bitten by forgetting the simple things at LEAST once (if not more).

Except for me, of course.

 

[crecords]

Help again, I purchased a keyboard cable and I plugged it in and the keyboard does not work. Is there something simple I am missing concerning the keyboard?
Also I was finally able to copy system files to a disk so I can boot without the external if needed.

 

[tdiaz]

What exactly did you purchase? Link?

 

[crecords]

http://www.ebay.com/itm/141089711230?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649


It was listed as an original cable.

 

[tdiaz]

I'd be pretty convinced that guy knows what he's selling.

The possibility that someone else has already plugged in a phone cable to it, and killed it.

It's pinned with +5 and GND on the edges and data in the middle. If a phone cable is used, that 5 and ground get swapped, and data gets reversed.

That usually nukes the keyboard controller, and even possibly something on the motherboard.

That looks original. Maybe check the wiring just to be sure it's actually connected. Also look in the connectors and see that you can see brass/copper wire hanging down in each, and not busted off or pushed up in from the wrong connector being pushed in.